2006 DTS performance headlight problems

I have now replaced both headlight bulbs in 2006 DTS original problem was flickering of both lights I bought two bulbs from a website called Philipsxenon.com seemed ligit for $100 for the pair they are a scam I replaced both bulbs a week ago driver one went out yesterday would not even turn on and wouldn't do anything I replaced the ballast with a used 1 thinking that was the problem turned out I put an old bulb back in now the light at least turns on so now I must order a pair of bulbs again from a legit website so that they match what a headache now I have an extra ballast laying around I am now 175 dollars into headlight problem before ordering new bulbs can anyone recommend a lower priced legit website for the headlight bulb replacement